DWT Holding Tank+ | Holding Tank Cleaner and Treatment

Item number: 7424930666632
£19.75 £16.46 (excl. VAT)

24 in stock

  • Organic product for grey water tank maintenance
  • Fights odors and blockages
  • Specially developed to break down organic sludge in the tank
  • Contents: 1 pack contains 150 grams

DWT Holding Tank+ | Holding Tank Maintenance | Plastic-Free!

Prevents odors and blockages in your holding tank.

DWT Holding Tank + is a highly effective, organic product in completely plastic-free packaging. It contains non-pathogenic bacteria and microorganisms that break down organic matter in the holding tank—without releasing unpleasant odors. This helps prevent foul-smelling wastewater.

This pack contains 150 grams, enough for approximately 10 treatments of 15 grams each (1 tablespoon). The packaging is fully compostable and can be disposed of with organic waste.

This product is 100% organic and carries no hazard label. Naturally, keep out of reach of children.

How do I use this holding tank maintenance product?

It’s easy to use. Simply check the size of your holding tank and adjust the dosage accordingly. For the correct dosage, please refer to the table under the “User Guide” tab.

How do I use Holding Tank + Holding Tank Maintenance?

The dosage is as follows:

  • Holding tanks up to 50 liters: use 15 grams (1 tablespoon) as a starting dose.
  • Holding tanks from 50 to 150 liters: use 30 grams (2 tablespoons) as a starting dose.
  • Holding tanks over 150 liters: use 45 grams (3 tablespoons) as a starting dose.

Repeat after each emptying or every 5 days.

Does Holding Tank + have a hazard label?

No, this product is completely organic and contains no chemicals. Therefore, it is free of hazard labels. Of course, it’s always wise to keep the product out of reach of children.

How much do I need for my holding tank?
That depends on the size of your holding tank. For the correct dosage, please refer to the table under the “User Guide” tab.

Customers rate us with a

9 out of 10

D Collins

19/03/2026
Suffering inexplicable sewer gas stench in our home … on mains and our utility company, various plumbers snd Drain specialists are baffled. we’re trying Drain Line Cleaner as an almost last resort. 1 x 4 doses so far and waiting for our 2nd delivery. Hoping for a result and will post further. Howver a 3 week lead time on amazon and c.£25 per bottle is almost as stinging as the stench.
Answer: Thank you for your review! I hope our K97 has helped in the meantime. If not, you are always welcome to contact us by email, mentioning your order number, so we can take a look at your situation!
Product: Roebic K97
Source: Google

Helen Nevin

03/02/2026
Quick delivery and good quality product
Product: Roebic K97
Source: Google

Chris Miller

18/01/2026
Fast delivery. Product very simple to use and, so far, seems to be doing the job that it is intended to do.
Product: Roebic K97
Source: Google

Mike

05/01/2026
I spoke with Richard who was able to advise me on the best products to use. Dispatched quickly and arrived well packaged.
Product: Bio-Recup LQD
Source: Kiyoh

Be Ge

28/12/2025
I had an obvious clog between soakaway and septic tank. Completely inaccessible to a human. This solved the problem almost instantly.
Product: Roebic K570
Source: Kiyoh

John

22-12-2025
Great product, good around service, quick delivery.
Product: Roebic K570
Source: Kiyoh

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